FujiNetChat - an IRC client for the Atari 8-bit with FujiNET.

For now, this is pretty rudimentary. It can currently:

- connect to an IRC server.

- complete the user/nick registration process, including handling the
  "nickname already in use" error (by adding _, 1, 2, etc to the
  user nick).

- respond to server PINGs.

- handles nick changes.

- multi-window display, with one screens' worth of scrollback per
  window.

- join up to 5 channels, each in its own window. more than 5 channels
  can be joined, but the extra ones get multiplexed together in the
  server window.

- send/receive channel messages.

- handles bold, underscore, italic, strikethrough formatting.

- "highlights" channel text that contains the user's nick.

- receive private messages (in a dedicated private messages window).

- create 'query' windows (PM with a specific user), send/receive PMs.

- server window to keep the chatty server messages from cluttering up
  the channel windows.

- input box at the bottom of the screen, allows editing and can
  handle up to 239 characters of input.

- status bar, shows the current window's number, name or channel,
  and which other windows have new text in them. disappears (replaced
  by the input box) when the user starts typing, and reappears when
  the user presses Enter to send the message/command, or Shift-Clear
  to abort it.

Differences from FujiChat:

- FujiChat does its own TCP/IP and DNS, using SLIP. FujiNetChat offloads
  the network stuff to the FujiNet device, freeing up memory for more
  client features (e.g. the multi-window display).

- FujiChat only supports joining one channel, and has no multi-window display.

- FujiChat can be used with software 80x25 or 64x32 text modes. FujiNetChat
  is (currently) 40 columns, using GR.0 style text mode.

- FujiNetChat allows you to type the { } ` ~ characters.
